Is Tendon Lengthening The Best Treatment For Diabetic Foot Ulcers?

Diabetic neuropathy results in tendon imbalance and decreased protective sensation.1,2 Tendon imbalance, especially Achilles or gastrocnemius-soleus tightness, causes or aggravates most foot problems.3-7 Achilles tendon or gastrocnemius-soleus tightness causes increased stress in the foot.8,9 This stress can cause a callus and a subsequent forefoot ulcer.8 Increased stress in the foot less commonly leads to the progressive deformity of Charcot arthropathy, most often in the midfoot. Midfoot Charcot arthropathy progresses from arthritis, ligamentous instability and/or fracture to arch collapse and/or subluxation. This in turn may lead to a midfoot plantar bony prominence and the possible development of a midfoot ulcer.10

Multiple authors have stated that tendon imbalance correction, particularly Achilles or gastroc-soleus tightness correction, can help address most foot problems.3-7,11-14 Accordingly, let us take a closer look at tendon lengthening in comparison to other forms of treatment for diabetic foot problems.

Foot ulcers commonly become infected and lead to amputation. Approximately 85 percent of patients with diabetes who undergo amputation have foot ulcers.15 Healing foot ulcers and preventing their recurrence could prevent most amputations in patients with diabetes. Foot ulcer treatment consists of managing infection, arterial problems and high stress in the foot.

We can treat infection with antibiotics and debridement. If the patient lacks both pedal pulses, vascular evaluation and treatment are recommended. Tendon lengthening can decrease stress in the foot.8

Achilles tendon or gastrocnemius-soleus lengthening can be helpful in primary or adjunctive treatment for most foot problems and usually heals foot ulcers.2,7-28 Treatment of foot ulcers with tendon lengthening has good support in the literature, both for healing ulcers and preventing recurrence.2,16-28 I previously published a detailed literature review on tendon lengthening for diabetic foot problems.27

When it comes to plantar toe ulcers, one may perform percutaneous flexor tenotomies. Surgeons may perform a gastrocnemius-soleus recession to help address diabetic ulcers plantar to the metatarsal heads or midfoot. One would add posterior tibialis tendon lengthening to gastrocnemius-soleus recession for ulcers plantar to the fifth metatarsal, and add peroneus longus lengthening for ulcers plantar to the first metatarsal.

Gastrocnemius-soleus recession results in fewer new postoperative heel ulcers than Achilles tendon lengthening.27,29 Tendon lengthening in the calf has fewer complications than bony procedures in the foot and ankle, especially if the patient has diabetes and/or has no pedal pulses.17,30-34 Tendon surgery seems preferable to bony procedures in those with diabetes, smokers and patients with foot ulcers, infection and/or without pedal pulses.

Comparing The Efficacy Of Tendon Lengthening To Other Treatments

Tendon lengthening heals more ulcers than wound care and total contact casting (TCC).27,35,36 A meta-analysis revealed that “good” wound care healed only 31 percent (142/458) of diabetic foot ulcers in five months.35 Total contact casts healed an average of 80 percent of diabetic foot ulcers.36 According to a literature review, over 90 percent of ulcers heal after tendon lengthening.27

Tendon lengthening has fewer complications and a much lower recurrence rate than TCC.19,27,29,30,37 Guyton reported a 30 percent complication rate with TCC.37 Mueller reported an 81 percent (21/26) recurrence of diabetic foot ulcers in two years after healing with TCC.19

Treatment of ulcers plantar to metatarsal heads with resection of the metatarsal head, metatarsal osteotomies and partial foot amputation all have high complication rates, including frequent transfer ulcers and amputation of the entire foot.27,31,32 Tendon lengthening heals more ulcers with fewer complications including fewer transfer ulcers and fewer amputations.2,16-28

Tendon lengthening appears to be an effective treatment and is my treatment of choice for diabetic toe ulcers and ulcers plantar to metatarsal heads and the midfoot.2,16-28 If ulcers recur, one can repeat tendon lengthening with good success.17,24,25 Tendon lengthening also helps heal transmetatarsal amputations and arterial forefoot wounds.18,38-47

Can Tendon Lengthening Have An Impact For Charcot Foot?

In one study on Charcot arthropathy, researchers noted that 36 percent of patients who had non-operative treatment had a progression of the deformity and 37 percent of patients treated with conservative care went on to ulceration.48 Tendon lengthening (gastrocnemius-soleus recession) heals most midfoot ulcers and frequently prevents recurrence and progression of the deformity of Charcot arthropathy.17

For these reasons, the recommendation that one use tendon lengthening (gastrocnemius-soleus recession) as the initial offloading treatment for Charcot arthropathy seems reasonable.49 In the few patients in whom tendon lengthening via gastrocnemius-soleus recession does not heal midfoot ulcers, or if the foot is unstable or too deformed for custom shoes and inserts, then surgeons can still perform bony procedures (exostectomy or fusion) later.

Further Insights On Tendon Lengthening And Gastroc Recession

General contraindications to Achilles lengthening and gastrocnemius-soleus recession are plantar heel ulcers, extensive necrosis and/or infection that necessitates amputation of the entire foot.

Increased stress in the foot can also cause deformity and foot pain including corns, calluses, clawtoes, plantar fasciitis, posterior tibial tendinitis, arch collapse, foot and ankle arthritis, Charcot arthropathy, Achilles tendinitis, metatarsalgia, and first metatarsophalangeal arthritis.4,6-8,11,12,17,50-57 Tendon lengthening can help address foot pain and deformity from these conditions.4,6,7,11,14,27,47,50-56 Patients with diabetes have a higher complication rate with foot and ankle surgery.58 Tendon lengthening via gastrocnemius-soleus recession has an advantage over most other surgeries for foot pain in patients with diabetes since it has a low complication rate and can also prevent foot ulcers from developing in the future.8,29,30

How Tendon Lengthening Stacks Up When It Comes To Evidence-Based Medicine

Most of the literature on the treatment of diabetic foot problems involves case series and personal opinion. The evidence for tendon lengthening for foot ulcers plantar to the metatarsal head includes a Level I study.19 There are also Level II studies as well as Level IV studies for tendon lengthening for ulcers plantar to the metatarsal head.2,16,21,23,24,26

There is lower Level IV evidence for tendon lengthening on plantar ulcers on the toes, midfoot and the distal end of transmetatarsal amputation stumps.17,18,23,25,27 There is similar Level IV evidence for the use of tendon lengthening for pain from plantar fasciitis, Achilles tendinitis, metatarsalgia.11,51,52,54-56 Finally, there are Level V studies on tendon lengthening for arthritis and posterior tibial tendinitis, and for tendon lengthening for calluses, corns, clawtoes and Charcot arthropathy.4,7,8,17,27,46,47,49,50,53

Final Notes

In my opinion, tendon lengthening should be included in the initial treatment for diabetic foot ulcers. Tendon lengthening may also be a helpful treatment for Charcot arthropathy, calluses and foot pain in patients with diabetes from other causes listed above.

Dr. Laborde is an Assistant Professor of Orthopaedic Surgery and Director of the Foot Clinic at the Louisiana State University Health Sciences Center in New Orleans.